Laser crystallization system and method of manufacturing display apparatus using the same

ABSTRACT

A laser crystallization system is disclosed. In one embodiment, the laser crystallization system includes i) a mother substrate including first, second, and third display regions sequentially arranged in a first direction and ii) a stage for supporting the mother substrate and moving in the first direction and in a second direction. The system also includes i) a first laser irradiation unit for irradiating a first laser beam having a width greater than or identical to a width of a side of one of the display regions in the first direction and ii) a second laser irradiation unit spaced apart from the first laser irradiation unit and irradiating a second laser beam having a width greater than or identical to the width of the side in the first direction. Furthermore, the first and second laser beams may correspond to widths of sides of the first and third display regions.

CROSS-REFERENCE TO RELATED PATENT APPLICATION

This application is a divisional application of U.S. application Ser.No. 13/272,114, filed on Oct. 12, 2011, which is incorporated byreference in its entirety. This application claims the benefit of KoreanPatent Application No. 10-2010-00107713, filed on Nov. 1, 2010, in theKorean Intellectual Property Office, the disclosure of which isincorporated herein in its entirety by reference.

BACKGROUND

1. Field

The described technology generally relates to a laser crystallizationsystem and a method of manufacturing a display apparatus using the lasercrystallization system, and more particularly, to a lasercrystallization system for improving characteristics of an active layerand easily forming the active layer, and a method of manufacturing adisplay apparatus using the laser crystallization system.

2. Description of the Related Technology

Recently, display devices have been replaced with portable thin filmtype flat displays. From among these flat displays, an organiclight-emitting display, which is self emissive, has a large viewingangle, good contrast characteristics, fast response speeds, and goodbrightness characteristics and requires a low driving voltage, and hasthus drawn attention as the next-generation display.

Such displays include active layers that are generally formed by formingamorphous semiconductor layers, performing a crystallization process onthe amorphous semiconductor layers, and patterning the crystallizedamorphous semiconductor layers. The crystallization process may beperformed by using various methods, and mainly by using laser.

Flat panel displays are generally formed in a plurality of displayregions formed on mother substrates for manufacturing processconvenience. Sizes of mother substrates have recently increasedaccording to demands for manufacturing efficiency and large-quantitiesof display devices.

However, a process of crystallizing an amorphous semiconductor layer ofa display region formed on a large-sized mother substrate is not easilyperformed, which restricts forming active layers having desiredcharacteristics.

SUMMARY

One inventive aspect is a laser crystallization system for improvingcharacteristics of an active layer and easily forming the active layer,and a method of manufacturing a display apparatus using the lasercrystallization system.

Another aspect is a laser crystallization system including: a mothersubstrate in which first, second, and third display regions in whichamorphous semiconductor layers are formed are sequentially arranged in afirst direction; a stage for supporting the mother substrate and movingin the first direction and in a second direction perpendicular to thefirst direction; a first laser irradiation unit for irradiating a firstlaser beam having a width greater than or identical to a width of a sideof one of the first, second, and third display regions in the firstdirection; and a second laser irradiation unit being spaced apart fromthe first laser irradiation unit and irradiating a second laser beamhaving a width greater than or identical to the width of the side of oneof the first, second, and third display regions in the first direction,wherein the first laser beam corresponds to a width of a side of thefirst display region in the first direction, and the second laser beamcorresponds to a width of a side of the third display region in thefirst direction.

The first laser irradiation unit may include a first shutter unit, thesecond laser irradiation unit comprises a second shutter unit, the widthof the first laser beam is controlled by the first shutter unit, and thewidth of the second laser beam is controlled by the second shutter unit.

The amorphous semiconductor layers may be crystallized by moving thestage in the second direction while the first laser irradiation unit andthe second laser irradiation unit are fixed.

The mother substrate may be an eighth generation substrate having awidth of 2500 mm in one direction, and a width of 2200 mm in anotherdirection.

The mother substrate may be an eighth generation substrate having awidth of 2200 mm in the first direction, and a width of 2500 mm in thesecond direction, and each of the first, second, and third displayregions has a size suitable for forming a 55 inch display apparatus.

The laser crystallization system may further include: fourth, fifth, andsixth display regions, wherein the fourth display region is disposed inparallel with the first display region in the second direction, thefifth display region is disposed in parallel with the second displayregion in the second direction, and the sixth display region is disposedin parallel with the third display region in the second direction.

The mother substrate may be an eighth generation substrate having awidth of 2500 mm in the first direction, and a width of 2200 mm in thesecond direction, and each of the first, second, and third displayregions has a size suitable for forming a 46 inch display apparatus.

The laser crystallization system may further include: fourth, fifth,sixth, seventh, and eighth display regions, wherein the fourth displayregion is disposed in parallel with the third display region in thefirst direction, the fifth display region is disposed in parallel withthe first display region in the second direction, the sixth displayregion is disposed in parallel with the second display region in thesecond direction, the seventh display region is disposed in parallelwith the third display region in the second direction, and the eighthdisplay region is disposed in parallel with the fourth display region inthe second direction.

A plurality of crystallization processes may be performed by maintaininga gap between the first laser irradiation unit and the second laserirradiation unit.

Another aspect is a method of manufacturing a display apparatus, themethod including: preparing a mother substrate in which at least first,second, and third display regions in which amorphous semiconductorlayers are formed are sequentially arranged in a first direction;disposing the mother substrate on a stage that moves in the firstdirection and in a second direction perpendicular to the firstdirection; forming an active layer by moving the stage in the seconddirection, irradiating a first laser beam corresponding to a width of aside of the first display region in the first direction from a firstlaser irradiation unit disposed on an upper portion of the mothersubstrate, irradiating a second laser beam corresponding to a width of aside of the third display region in the first direction from a secondlaser irradiation unit disposed on the upper portion of the mothersubstrate, and crystallizing the amorphous semiconductor layers of thefirst display region and the third display region; and forming thedisplay device on an upper portion of the active layer.

A width of the first laser beam may be controlled by a first shutterunit included in the first laser irradiation unit, and a width of thesecond laser beam may be controlled by a second shutter unit included inthe second laser irradiation unit.

The crystallizing of the amorphous semiconductor layers may include:moving the stage in the second direction while the first laserirradiation unit and the second laser irradiation unit are fixed.

The method may further include: after crystallizing the amorphoussemiconductor layers of the first display region and the third displayregion, moving the stage in the first direction, disposing the firstlaser beam or the second laser beam to correspond to the second displayregion, moving the stage in the second direction, and crystallizing theamorphous semiconductor layer of the second display region.

The mother substrate may be an eighth generation substrate having awidth of 2500 mm in one direction, and a width of 2200 mm in anotherdirection.

The mother substrate may be an eighth generation substrate having awidth of 2200 mm in the first direction, and a width of 2500 mm in thesecond direction, and each of the first, second, and third displayregions has a size suitable for forming a 55 inch display apparatus.

The method may further include: fourth, fifth, and sixth displayregions, wherein the fourth display region is disposed in parallel withthe first display region in the second direction, the fifth displayregion is disposed in parallel with the second display region in thesecond direction, and the sixth display region is disposed in parallelwith the third display region in the second direction, wherein theamorphous semiconductor layers of the fourth display region and thesixth display region are crystallized by continuously moving the stagein the second direction after crystallizing the amorphous semiconductorlayers of the first display region and the third display region.

The method may further include: after crystallizing the amorphoussemiconductor layers of the first display region, the third displayregion, the fourth display region, and the sixth display region, movingthe stage in the first direction, disposing the first laser beam or thesecond laser beam to correspond to the second display region, moving thestage in the second direction, crystallizing the amorphous semiconductorlayer of the second display region, continuously moving the stage in thesecond direction, and crystallizing the amorphous semiconductor layer ofthe fifth display region.

The mother substrate may be an eighth generation substrate having awidth of 2500 mm in the first direction, and a width of 2200 mm in thesecond direction, and each of the first, second, and third displayregions has a size suitable for forming a 46 inch display apparatus.

The method may further include: fourth, fifth, sixth, seventh, andeighth display regions, wherein the fourth display region is disposed inparallel with the third display region in the first direction, whereinthe fifth display region is disposed in parallel with the first displayregion in the second direction, the sixth display region is disposed inparallel with the second display region in the second direction, theseventh display region is disposed in parallel with the third displayregion in the second direction, and the eighth display region isdisposed in parallel with the fourth display region in the seconddirection, wherein the amorphous semiconductor layers of the fifthdisplay region and the seventh display region are crystallized bycontinuously moving the stage in the second direction aftercrystallizing the amorphous semiconductor layers of the first displayregion and the third display region.

The method may further include: after crystallizing the amorphoussemiconductor layers of the first display region, the third displayregion, the fifth display region, and the seventh display region, movingthe stage in the first direction, disposing the first laser beam and thesecond laser beam to correspond to the second display region and thefourth display region, respectively, moving the stage in the seconddirection, crystallizing the amorphous semiconductor layers of thesecond display region and the fourth display region, continuously movingthe stage in the second direction, and crystallizing the amorphoussemiconductor layers of the sixth display region and the eighth displayregion.

A plurality of crystallization processes may be performed by maintaininga gap between the first laser irradiation unit and the second laserirradiation unit.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic perspective view illustrating a lasercrystallization system and a mother substrate crystallized by using thelaser crystallization system, according to an embodiment.

FIG. 2 is a plan view illustrating the mother substrate of FIG. 1.

FIG. 3 is a plan view illustrating a mother substrate crystallized byusing the laser crystallization system of FIG. 1, according to anotherembodiment.

FIG. 4 is a schematic perspective view illustrating a mother panel for afinally manufactured display apparatus after performing acrystallization process by using the laser crystallization system ofFIG. 1, according to an embodiment.

FIG. 5 is a cross-sectional view of the mother panel taken along line Aof FIG.

DETAILED DESCRIPTION

Embodiments will now be described more fully with reference to theaccompanying drawings.

FIG. 1 is a schematic perspective view illustrating a lasercrystallization system 1000 and a mother substrate 101 crystallized byusing the laser crystallization system, according to an embodiment. FIG.2 is a plan view illustrating the mother substrate 101 of FIG. 1.

Referring to FIGS. 1 and 2, the laser crystallization system 1000includes the mother substrate 101, a stage 1100, a first laserirradiation unit 1210, and a second laser irradiation unit 1220.

The stage 1100 includes a driving unit (not shown) so that the stage1100 is driven in a first direction (e.g., in a direction X of FIG. 1)and in a second direction (e.g., in a direction Y of FIG. 1).

The mother substrate 101 is disposed on the stage 1100. In oneembodiment, the mother substrate 101 has an eighth generation size tomanufacture six 55 inch display apparatuses in a single process. In thisembodiment, a length L of the first direction of the mother substrate101 is about 2200 mm, and a width W of the second direction of themother substrate 101 is about 2500 mm.

The mother substrate 101 may be formed of transparent glass of which amain component is SiO₂. However, the mother substrate 101 is not limitedthereto. For example, the mother substrate 101 may be formed of atransparent plastic. In this regard, the plastic material used forforming the mother substrate 101 may be an insulating organic materialselected from the group consisting of polyethersulphone (PES),polyacrylate (PAR), polyetherimide (PEI), polyethyelenen napthalate(PEN), polyethyeleneterepthalate (PET), polyphenylene sulfide (PPS),polyallylate, polyimide, polycarbonate (PC), cellulose triacetate (TAC),and cellulose acetate propionate (CAP).

The mother substrate 101 includes a plurality of display regions 102 a,102 b, 102 c, 102 d, 102 e, and 102 f. Although not shown, amorphoussemiconductor layers are formed on the display regions 102 a-102 f. Morespecifically, the amorphous semiconductor layers may contain amorphoussilicon.

The display regions 102 a-102 f correspond to a plurality of displayapparatuses that will be formed through a subsequent process. That is,each of the display apparatuses that are finally formed through thesubsequent process includes one of the display regions 102 a-102 f. Eachdisplay apparatus includes circuit units (not shown) that will be formedin spaces D1, D2, D3, and D4 between the display regions 102 a-102 f.Each display apparatus is divided by cutting predetermined regions ofthe spaces D1-D4.

Widths of the spaces D1-D4 may be determined according to processconditions.

The display regions 102 a-102 f are defined as the first display region102 a, the second display region 102 b, the third display region 102 c,the fourth display region 102 d, the fifth display region 102 e, and thesixth display region 102 f.

The first display region 102 a, the second display region 102 b, and thethird display region 102 c are sequentially arranged on the upper areaof the mother substrate 101 in the first direction. The fourth displayregion 102 d, the fifth display region 102 e, and the sixth displayregion 102 f are sequentially arranged on the lower area of the mothersubstrate 101 in the second direction. The first display region 102 aand the fourth display region 102 d are disposed substantially inparallel with each other in the second direction. The second displayregion 102 b and the fifth display region 102 e are disposedsubstantially in parallel with each other in the second direction. Thethird display region 102 c and the sixth display region 102 f aredisposed substantially in parallel with each other in the seconddirection.

In one embodiment, all of the display regions 102 a-102 f havesubstantially the same shape and size. In one embodiment, each of thedisplay regions 102 a-102 f has a shape and size corresponding to a 55inch display apparatus.

For example, the length of the first display region 102 a in the firstdirection may be about 703 mm, and the width of the first display region102 a in the second direction may be about 1232.8 mm. In anotherembodiment, the length and the width may slightly differ according todesign criteria of a circuit region to be formed around the firstdisplay region 102 a.

In one embodiment, the second to fifth display regions 102 b-102 f areformed to have substantially the same size as the first display region102 a.

The first laser irradiation unit 1210 and the second laser irradiationunit 1220 are disposed on the mother substrate 101. The first and secondlaser irradiation units 1210 and 1220 are spaced apart from each otherby a gap G. The first laser irradiation unit 1210 includes a firstshutter unit 1211. The second laser irradiation unit 1220 includes asecond shutter unit 1221.

The first laser irradiation unit 1210 irradiates a first laser beam 1215toward the first display region 102 a. The first laser beam 1215 has awidth P1 in the first direction. The width P1 of the first laser beam1215 is obtained by reducing a width S1 by the first shutter unit 1211.That is, the maximum beam width of the first laser irradiation unit 1210is S1+P1. The maximum beam width S1+P1 is about 740 mm.

Furthermore, the size of the width S1 may be controlled by the firstshutter unit 1211 in various ways. Although a right-side width of thefirst laser beam 1215 is reduced due to the first shutter unit 1211 inFIG. 2, a left-side width of the first laser beam 1215 may be reduceddue to the first shutter unit 1211.

The second laser irradiation unit 1220 irradiates a second laser beam1225 toward the third display region 102 c. The second laser beam 1225has a width P2 in the first direction. The width P2 of the second laserbeam 1225 is obtained by reducing a width S2 by the second shutter unit1221. That is, the maximum beam width of the second laser irradiationunit 1220 is S2+P2. The maximum beam width S2+P2 is about 740 mm.

Furthermore, the size of the width S2 may be controlled by the secondshutter unit 1221 in various ways. Although a left-side width of thesecond laser beam 1225 is reduced due to the second shutter unit 1221 inFIG. 2, a right-side width of the second laser beam 1225 may be reduceddue to the second shutter unit 1221.

The width P1 of the first laser beam 1215 is greater than the width ofthe first display region 102 a in the first direction. For example, thewidth P1 of the first laser beam 1215 is greater than about 703 mm.

Furthermore, the first laser irradiation unit 1210 is controlled in sucha way that the first laser beam 1215 substantially overlaps with theentire width of the first display region 102 a in the first direction.

In one embodiment, the width P2 of the second laser beam 1225 is greaterthan the width of the third display region 102 c in the first direction.For example, the width P2 of the second laser beam 1225 is greater thanabout 703 mm.

Furthermore, the second laser irradiation unit 1220 is controlled insuch a way that the second laser beam 1225 substantially overlaps withthe entire width of the third display region 102 c in the firstdirection.

The first laser irradiation unit 1210 and the second laser irradiationunit 1220 are spaced apart from each other by the gap G. The gap G maybe approximately about 650 mm.

In one embodiment, the first laser beam 1215 and the second laser beam1225 are not irradiated onto the second display region 102 b disposedbetween the first display region 102 a and the third display region 102c by the gap G and the first shutter unit 1211 and the second shutterunit 1221.

The first laser irradiation unit 1210 and the second laser irradiationunit 1220 may be fixed and move the stage 1100 in a scan direction S,i.e. in the second direction. For example, the first laser beam 1215sequentially crystallizes the amorphous semiconductor layers formed onthe first display region 102 a and the fourth display region 102 d.Furthermore, the second laser beam 1225 that is substantiallysimultaneously irradiated with the first laser beam 1215 sequentiallycrystallizes the amorphous semiconductor layers formed on the thirddisplay region 102 c and the sixth display region 102 f. That is, whenthe stage 1100 moves, a crystallization process is substantiallysimultaneously performed in the first display region 102 a and the thirddisplay region 102 c, and is substantially simultaneously performed inthe fourth display region 102 d and the sixth display region 102 f.

The crystallization process is performed in the second display region102 b and the fifth display region 102 e after moving the stage 1100 inthe first direction, arranging the first laser beam 1215 or the secondlaser beam 1225 to correspond to the second display region 102 b, andmoving the stage 1100 in the scan direction S. In this regard, the firstlaser beam 1215 or the second laser beam 1225 that does not correspondto the second display region 102 b may be shut off by using a shutterunit.

FIG. 3 is a plan view illustrating the mother substrate 101 crystallizedby using the laser crystallization system 1000 of FIG. 1, according toanother embodiment.

Referring to FIG. 3, the laser crystallization system 1000 is the sameas the laser crystallization system 1000 of FIG. 1, except that thefirst shutter unit 1211 and the second shutter unit 1221 are differentfrom those described with reference to FIGS. 1 and 2. More specifically,the size of the width S1 of a beam that is reduced by the first shutterunit 1211 of FIG. 3, and the size and position of the width S2 of thebeam that is reduced by the second shutter unit 1221 are different fromthose described with reference to FIGS. 1 and 2.

The mother substrate 101 is disposed on the stage 1100. In oneembodiment, the mother substrate 101 has an eighth generation size tomanufacture eight 46 inch display apparatuses in a single process, andis substantially the same size as the mother substrate 101 of FIGS. 1and 2. In this embodiment, the mother substrate 101 is obtained byrotating the mother substrate 101 of FIGS. 1 and 2, wherein, a width Wof a first direction of the mother substrate 101 is about 2500 mm, and alength L of a second direction of the mother substrate 101 is about 2200mm.

The mother substrate 101 includes a plurality of display regions 103a-103 h. Although not shown, amorphous semiconductor layers are formedon the display regions—103 h. More specifically, the amorphoussemiconductor layers may contain amorphous silicon.

The display regions 103 a-103 h correspond to a plurality of displayapparatuses to be formed through a subsequent process. That is, each ofthe display apparatuses that are finally formed through the subsequentprocess includes one of the display regions 103 a-103 h. Each displayapparatus includes circuit units (not shown) to be formed in spacesE1-E5 between the display regions 103 a-103 h. Each display apparatus isdivided by cutting predetermined regions of the spaces E1-E5. Widths ofthe spaces E1-E5 may be determined according to process conditions.

The display regions 103 a-103 h are defined as the first display region103 a, the second display region 103 b, the third display region 103 c,the fourth display region 103 d, the fifth display region 103 e, thesixth display region 103 f, the seventh display region 103 g, and theeighth display region 103 h.

The first to fourth display regions 103 a-103 d are sequentiallyarranged on the upper area of the mother substrate 101 in the firstdirection. The fifth to eighth display regions 103 e-103 h aresequentially arranged on the lower area of the mother substrate 101 inthe first direction. The first display region 103 a and the fifthdisplay region 103 e are disposed substantially in parallel with eachother in the second direction. The second display region 103 b and thesixth display region 103 f are disposed substantially in parallel witheach other in the second direction. The third display region 103 c andthe seventh display region 103 g are disposed substantially in parallelwith each other in the second direction. The fourth display region 103 dand the eighth display region 103 h are disposed substantially inparallel with each other in the second direction.

In one embodiment, all of the display regions 103 a-103 h havesubstantially the same shape and size. In one embodiment, each of thedisplay regions 103 a-103 h has a shape and size corresponding to a 46inch display apparatus.

For example, the length of the first display region 103 a in the firstdirection may be about 591.3 mm, and the width of the first displayregion 103 a in the second direction may be about 1041.35 mm. In anotherembodiment, the length and the width may slightly differ according todesign criteria of a circuit region to be formed around the firstdisplay region 103 a.

In one embodiment, the second to eighth display regions 103 b-103 h areformed to have substantially the same size as the first display region103 a.

The first laser irradiation unit 1210 and the second laser irradiationunit 1220 are disposed on the mother substrate 101. The first laserirradiation unit 1210 and the second laser irradiation unit 1220 arespaced apart from each other by the gap G that is the same as shown inFIG. 1. For example, the gap G is approximately about 650 mm, asdescribed above.

The first laser irradiation unit 1210 irradiates the first laser beam1215 toward the first display region 103 a. The first laser beam 1215has the width P1 in the first direction. The width P1 of the first laserbeam 1215 is obtained by reducing the width S1 by the first shutter unit1211. The width P1 of the first laser beam 1215 is smaller than thewidth P1 of the first laser beam 1215 of FIGS. 1 and 2. That is, thewidth S1 of the first shutter unit 1211 is greater than the width S1 ofFIGS. 1 and 2.

That is, the maximum beam width of the first laser irradiation unit 1210is S1+P1 which is the same as shown in FIGS. 1 and 2. The maximum beamwidth S1+P1 is about 740 mm.

Furthermore, the size of the width S1 may be controlled in various waysby the first shutter unit 1211. Although a right-side width of the firstlaser beam 1215 is reduced due to the first shutter unit 1211 in FIG. 3,a left-side width of the first laser beam 1215 may be reduced due to thefirst shutter unit 1211.

The second laser irradiation unit 1220 irradiates the second laser beam1225 toward the third display region 103 c. The second laser beam 1225has the width P2 in the first direction. The width P2 of the secondlaser beam 1225 is obtained by reducing the width S2 by the secondshutter unit 1221. The width P2 of the second laser beam 1225 is smallerthan the width P2 of the second laser beam 1225 of FIGS. 1 and 2. Thatis, the width S2 of the second shutter unit 1221 is greater than thewidth S2 of FIGS. 1 and 2.

The maximum beam width of the second laser irradiation unit 1220 isS2+P2, which is the same as shown in FIGS. 1 and 2. The maximum beamwidth S2+P2 is about 740 mm.

Furthermore, the size of the width S2 may be controlled by the secondshutter unit 1221 in various ways. Although a right-side width of thesecond laser beam 1225 is reduced due to the second shutter unit 1221 inFIG. 3, a left-side width of the second laser beam 1225 may be reduceddue to the second shutter unit 1221.

The width P1 of the first laser beam 1215 is greater than the width ofthe first display region 103 a in the first direction. For example, thewidth P1 of the first laser beam 1215 is greater than about 591.3 mm.

Furthermore, the first laser irradiation unit 1210 is controlled in sucha way that the first laser beam 1215 overlaps the entire width of thefirst display region 103 a in the first direction.

The width P2 of the second laser beam 1225 is greater than the width ofthe third display region 103 c in the first direction. For example, thewidth P2 of the second laser beam 1225 is greater than about 591.3 mm.

Furthermore, the second laser irradiation unit 1220 is controlled insuch a way that the second laser beam 1225 overlaps the entire width ofthe third display region 103 c in the first direction.

The first laser beam 1215 and the second laser beam 1225 are notirradiated onto the second display region 103 b disposed between thefirst display region 103 a and the third display region 103 c by the gapG and the first shutter unit 1211 and the second shutter unit 1221.

The first laser irradiation unit 1210 and the second laser irradiationunit 1220 are fixed and move the stage 1100 in a scan direction S, i.e.in the second direction. Accordingly, the first laser beam 1215sequentially crystallizes the amorphous semiconductor layers formed onthe first display region 103 a and the fifth display region 103 e.Furthermore, the second laser beam 1225 that is substantiallysimultaneously irradiated with the first laser beam 1215 sequentiallycrystallizes the amorphous semiconductor layers formed on the thirddisplay region 103 c and the seventh display region 103 g. That is, whenthe stage 1100 moves, a crystallization process is substantiallysimultaneously performed in the first display region 103 a and the thirddisplay region 103 c, and is substantially simultaneously performed inthe fifth display region 103 e and the seventh display region 103 g.

The crystallization process is performed in the second display region103 b and the fourth display region 103 d after moving the stage 1100 inthe first direction, arranging the first laser beam 1215 and the secondlaser beam 1225 to correspond to the second display region 103 b and thefourth display region 103 d, respectively, and moving the stage 1100 inthe scan direction S, i.e. in the second direction.

The laser crystallization system 1000 of the present embodiment is usedto continuously perform the crystallization process by irradiating abeam having a width corresponding to a width of one side of each displayregion formed on the mother substrate 101, thereby improvingcharacteristics of a crystallized semiconductor layer. Furthermore, thecrystallized semiconductor layer having uniform characteristics iseasily formed.

The crystallization process is performed by substantially simultaneouslyirradiating the first laser beam 1215 and the second laser beam 1225,thereby improving process convenience.

The crystallization process is performed by moving the stage 1100 onwhich the mother substrate 101 is disposed, while the first laser beam1210 and the second laser beam 1220 that are not easily controlled arefixed, thereby increasing improvement of the characteristics of thecrystallized semiconductor layer.

In particular, the first laser beam 1210 and the second laser beam 1220are fixed apart from each other by the gap G. The first laser beam 1210and the second laser beam 1220 include the first shutter unit 1211 andthe second shutter unit 1221, respectively. The one lasercrystallization system 1000 can perform a crystallization process forforming a 55 inch display apparatus and a crystallization process forforming a 46 inch display apparatus in an eighth generation mothersubstrate by fixing the first laser beam 1210 and the second laser beam1220 that are spaced apart from each other by the gap G and controllingthe first shutter unit 1211 and the second shutter unit 1221. Thecrystallization processes for forming the display apparatuses having thetwo different sizes are performed without moving the first laser beam1210 and the second laser beam 1220, thereby preventing a variation of alaser beam due to the movements of the first laser beam 1210 and thesecond laser beam 1220, and a reduction of the crystallizationcharacteristics caused by the variation of the laser beam.

Accordingly, a process of manufacturing display apparatuses of varioussizes is easy in the eighth generation mother substrate that is anext-generation mother substrate for forming a large-sized displayapparatus.

FIG. 4 is a schematic perspective view illustrating the mother panel 190for a finally manufactured display apparatus after performing acrystallization process by using the laser crystallization system ofFIG. 1, according to an embodiment. FIG. 5 is a cross-sectional view ofthe mother panel 190 taken along line A of FIG. 4.

Referring to FIGS. 4 and 5, a buffer layer 111 is formed on the mothersubstrate 101 before an amorphous silicon layer is formed thereon. Thebuffer layer 111 may contain SiO₂ or SiN_(x). The buffer layer 111provides an upper portion of the mother substrate 101 with a planarsurface, and prevents moisture and impurities from permeating into themother substrate 101.

An active layer 112 having a predetermined pattern is formed on thebuffer layer 111. The active layer 112 is formed by forming theamorphous silicon layer and crystallizing the amorphous silicon layer byusing the laser crystallization system 1000 as described above.

A gate insulation layer 113 is formed on an upper portion of the activelayer 112. A gate electrode 114 is formed in a predetermined region ofan upper portion of the gate insulation layer 113. The gate electrode114 may be formed of a metal or a metal alloy, such as Au, Ag, Cu, Ni,Pt, Pd, Al, Mo, or an Al:Nd alloy, an Mo:W alloy, etc., but the presentinvention is not limited thereto.

An interlayer insulation layer 115 is formed on an upper portion of thegate electrode 114 through which a predetermined region of the activelayer 112 is exposed. A source electrode 116 and a drain electrode 117are formed to contact the exposed region of the active layer 112.

A passivation layer 118 is formed to cover the source electrode 116 andthe drain electrode 117. An organic light emitting device 120 is formedon the passivation layer 118. Although the organic light emitting device120 is used as a display device in the present embodiment, a variety ofdisplay devices including a liquid crystal device, etc. may be used.

The organic light emitting device 120 includes a first electrode 121, asecond electrode 122, and an intermediate layer 123.

More specifically, the first electrode 121 is formed on the passivationlayer 118. The passivation layer 118 is formed to expose the drainelectrode 117. The first electrode 121 is electrically connected to theexposed drain electrode 117.

A pixel definition layer 119 is formed on the first electrode 121. Thepixel definition layer 119 includes a variety of insulation materialsand is formed to expose a predetermined region of the first electrode121.

The intermediate layer 123 is formed on the first electrode 121. Theintermediate layer 123 includes an organic emission layer (not shown)that generates visible light. The second electrode 122 is formed on theintermediate layer 123. If a voltage is applied through the firstelectrode 121 and the second electrode 122, the visible light isrealized in the organic emission layer of the intermediate layer 123.

A sealing member 170 is disposed on the second electrode 122 and thusthe mother panel 190 for the display device is finally formed. Althoughnot shown, six 55 inch display apparatuses or eight 46 inch displayapparatuses can be formed by cutting the mother panel 190 for thedisplay apparatus.

The sealing member 170 is formed to protect the intermediate layer 123and the other layers from external moisture or oxygen and is formed of atransparent material. To this end, the sealing member 170 may includeglass, plastic, or a plurality of stacked layers including organic andinorganic materials.

Although the sealing member 170 is spaced apart from the secondelectrode 122 in FIG. 5, the sealing member 170 and the second electrode122 may contact each other.

The active layer 112 of the present embodiment is formed by using thelaser crystallization system 1000 and has uniform characteristicsthroughout the mother panel 190 for the display apparatus. Furthermore,a crystallization process is continuously performed while the firstlaser irradiation unit 1210 and the second laser irradiation unit 1220that irradiate a laser beam are fixed, and thus the active layer 112 hascontinuous and improved electrical characteristics.

As described above, according to the laser crystallization system and amethod of manufacturing a display apparatus using the lasercrystallization system, characteristics of an active layer are improvedand the active layer is easily formed.

While the disclosed embodiments have been shown and described withreference to the accompanying drawings, it will be understood by thoseof ordinary skill in the art that various changes in form and detailsmay be made therein without departing from the spirit and scope of thefollowing claims.

What is claimed is:
 1. A laser crystallization system comprising: amother substrate in which first, second, and third display regions aresequentially arranged in a first direction, wherein amorphoussemiconductor layers are formed in each of the display regions; a stageconfigured to support the mother substrate and move in the firstdirection and in a second direction substantially perpendicular to thefirst direction; a first laser irradiation unit configured to irradiatea first laser beam having a width greater than or substantiallyidentical to the width of a side of one of the first, second, and thirddisplay regions in the first direction; and a second laser irradiationunit being spaced apart from the first laser irradiation unit andconfigured to irradiate a second laser beam having a width greater thanor substantially identical to the width of the side of one of the first,second, and third display regions in the first direction, wherein thefirst laser beam corresponds to the width of a side of the first displayregion in the first direction, and wherein the second laser beamcorresponds to the width of a side of the third display region in thefirst direction.
 2. The laser crystallization system of claim 1, whereinthe first laser irradiation unit comprises a first shutter unitconfigured to control the width of the first laser beam, and wherein thesecond laser irradiation unit comprises a second shutter unit configuredto control the width of the second laser beam.
 3. The lasercrystallization system of claim 1, wherein the first and second laserirradiation units are configured to crystallize the amorphoussemiconductor layers by moving the stage in the second direction whilethe laser irradiation units are fixed.
 4. The laser crystallizationsystem of claim 1, wherein the mother substrate is an eighth generationsubstrate having a width of about 2500 mm in one direction, and a widthof about 2200 mm in another direction.
 5. The laser crystallizationsystem of claim 1, wherein the mother substrate is an eighth generationsubstrate having a width of about 2200 mm in the first direction, and awidth of about 2500 mm in the second direction, and wherein each of thefirst, second, and third display regions has a size suitable for forminga 55 inch display apparatus.
 6. The laser crystallization system ofclaim 5, further comprising: fourth, fifth, and sixth display regions,wherein the fourth display region is disposed substantially in parallelwith the first display region in the second direction, wherein the fifthdisplay region is disposed substantially in parallel with the seconddisplay region in the second direction, and wherein the sixth displayregion is disposed substantially in parallel with the third displayregion in the second direction.
 7. The laser crystallization system ofclaim 1, wherein the mother substrate is an eighth generation substratehaving a width of about 2500 mm in the first direction, and a width ofabout 2200 mm in the second direction, and wherein each of the first,second, and third display regions has a size suitable for forming a 46inch display apparatus.
 8. The laser crystallization system of claim 7,further comprising: fourth, fifth, sixth, seventh, and eighth displayregions, wherein the fourth display region is disposed substantially inparallel with the third display region in the first direction, whereinthe fifth display region is disposed substantially in parallel with thefirst display region in the second direction, wherein the sixth displayregion is disposed substantially in parallel with the second displayregion in the second direction, wherein the seventh display region isdisposed substantially in parallel with the third display region in thesecond direction, and wherein the eighth display region is disposedsubstantially in parallel with the fourth display region in the seconddirection.
 9. The laser crystallization system of claim 1, wherein a gapbetween the first laser irradiation unit and the second laserirradiation unit is maintained while a plurality of crystallizationprocesses are performed.
 10. The laser crystallization system of claim1, wherein each of the first, second, and third display regionscorresponds to a display apparatus configured to display an image. 11.The laser crystallization system of claim 1, wherein the second displayregion is interposed between the first and third display regions,wherein neither of the first and second laser irradiation units isconfigured to irradiate the first or second laser beam onto the seconddisplay region while irradiating the first and second laser beams to thefirst and third display regions.